64 Studio is a collection of native free software
for digital content creation on x86_64 hardware
(AMD's 64-bit CPUs and Intel's EM64T chips). It's
based on the pure 64 port of Debian GNU/Linux, but
with a specialised package selection and lots of
other customisations. The distribution includes
the Linux kernel with realtime preemption patches,
the GNOME desktop, and a selection of creative
applications, covering audio and music, 2D and 3D
graphics, and publishing for the Web and print. It
also includes Internet and office tools that a
creative user is likely to need for their daily work.

The 64 Studio Platform Development Kit (PDK) is a
version control system for GNU/Linux
distributions, allowing the creation and
management of many different projects, based on
Debian and Ubuntu sources. PDK is written in
Python, and the source code is well commented and
contains documented examples.

ALT Linux is a set of Linux distributions that are
based on Sisyphus, an APT-enabled RPM package
repository that aims to achieve feature
completeness, usability, and security in a
sensible and manageable mixture.

The AROS Research Operating System is an effort to implement an Open Source and portable operating system that is compatible with AmigaOS(TM) 3.1. It was originally meant to be a direct reimplementation, but AROS currently has features which do not exist in AmigaOS(TM).

AWOS is a fast, highly optimized operating
environment that strives to be POSIX compliant.
Care is taken to ensure that it can run on very
old hardware, yet still allow it to take advantage
of the newest platforms.

Admelix is a live CD distribution based on Ubuntu
Linux with tools for business administration. Its
main objective is to guide managers of small and
medium-size businesses towards GNU/Linux and open
source software. In addition to the live CD, the
project's Web site provides information about open
and free tools for business administration.